Double-carbon material reinforced gallium-based composite heat-conducting paste and preparation method thereof
By combining modified diamond and modified carbon fiber with gallium-based liquid metal to form a titanium carbide coating, the problem of poor wettability of liquid metal-based thermal interface materials is solved, and the thermal conductivity and heat dissipation efficiency are improved.
Patent Information
- Application Number
- CN202511085790.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-04
- Publication Date
- 2025-10-31
AI Technical Summary
Existing liquid metal-based thermal interface materials have poor wettability in microelectronic packaging, resulting in material instability and an inability to effectively meet heat dissipation requirements.
Modified diamond and modified carbon fiber are combined with gallium-based liquid metal, and a titanium carbide coating is formed through metallization modification to improve wettability. The mixture is then mixed in an air environment to promote the composite, forming a gallium-based composite thermal paste reinforced with dual carbon materials.
It improves the wettability and thermal conductivity of thermal interface materials, enhances the heat dissipation efficiency between electronic components and heat sinks, and solves the problem of material instability caused by poor wettability.
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Figure CN120865851A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of thermal interface materials technology, specifically, it relates to a gallium-based composite thermal grease reinforced with dual carbon materials and its preparation method. Background Technology
[0002] As microelectronics manufacturing processes advance to below 3nm, chip transistor density has exceeded tens of billions, and device packaging thickness has decreased to the millimeter scale. With the combination of miniaturization and high computing power, the heat flux density per unit area exceeds 1000W / cm². 2 This exceeds the heat dissipation limits of traditional silicon-based devices. Studies have shown that for every 15°C increase in the temperature of electronic components, the probability of electromigration failure increases by 200%, while the increase in leakage current leads to a surge in dynamic power consumption of more than 30%, severely restricting the stability of high-frequency signal transmission. Therefore, a breakthrough heat dissipation solution is urgently needed.
[0003] To effectively improve the heat dissipation capacity of components within microelectronic packages, in addition to high thermal conductivity heat sinks and high heat dissipation efficiency radiators, thermal interface materials along the heat dissipation path of the package structure can fill the gaps between solid and solid interfaces, reduce the contact thermal resistance between electronic components and radiators, and increase the actual contact area and heat conduction path. This is a crucial aspect of thermal management. Liquid metal-based thermal interface materials have inherent advantages, exhibiting higher thermal conductivity compared to traditional polymer-based thermal interface materials. However, their liquid state is prone to overflow during repeated thermal cycling. Current research uses low-melting-point liquid metals as thermal interface materials, mixed with carbon materials, which can improve thermal conductivity to some extent and prevent liquid metal overflow. However, liquid metals have high surface tension, resulting in poor wettability between carbon materials and liquid metals, leaving large gaps with a small amount of air filling the gaps. Therefore, the thermal conductivity of the material needs further improvement.
[0004] To address this issue, a method for preparing and applying a gallium-based composite thermal paste with good wettability, reinforced by dual carbon materials, is proposed to meet the heat dissipation requirements of microelectronic components. Summary of the Invention
[0005] To address the problems in the prior art, the present invention aims to provide a method for preparing a gallium-based composite thermal grease reinforced with dual carbon materials, thereby developing a thermal grease with good wettability and excellent thermal conductivity. This solves the problem that poor wettability leads to material instability, causing the thermal interface material to fail to meet heat dissipation requirements, and thus improves the heat dissipation efficiency between electronic components and heat sinks.
[0006] The technical solution of this invention is as follows:
[0007] A dual-carbon material reinforced gallium-based composite thermal grease, the thermal grease comprising gallium-based liquid metal and inorganic thermally conductive carbon material filler.
[0008] Furthermore, the gallium-based liquid metal is one or more of gallium, indium, tin, zinc, antimony, bismuth, cadmium, and lead.
[0009] Furthermore, the inorganic thermally conductive carbon material filler is modified diamond and modified carbon fiber; wherein, the modified diamond includes diamond microparticles and a metal coating or metal carbide coating covering the surface of the diamond microparticles, and the modified carbon fiber includes carbon fiber whiskers and a metal coating or metal carbide coating covering the surface of the carbon fiber whiskers.
[0010] Furthermore, the metal coating is at least one of titanium, chromium, and tungsten, and the metal carbide coating is at least one of titanium carbide, chromium carbide, and tungsten carbide.
[0011] Furthermore, the raw materials of the gallium-based liquid metal are composed of liquid gallium, indium particles, and tin powder in a mass ratio of 65-70:18-23:10-15, and the volume ratio of the gallium-based liquid metal to the diamond and the carbon fiber is 50-70:30-50:2-10.
[0012] The preparation method of the dual-carbon material reinforced gallium-based composite thermal conductive paste includes the following steps:
[0013] Preparation of Si gallium-based liquid metal;
[0014] Liquid gallium, indium granules, and tin powder are weighed, mixed, heated, and stirred to obtain gallium-based liquid metal. Specifically, liquid gallium, indium granules, and tin powder with high thermal conductivity are selected, mixed in a mass ratio of 65-70:18-23:10-15, and placed in a crucible. Under a certain environment, the mixture is heated and stirred to a specified temperature to form gallium-based liquid metal. After cooling to room temperature, the mixture is stored in an oxygen-free environment for later use. This liquid metal has excellent thermal conductivity and fluidity at room temperature.
[0015] S2 metallization modification;
[0016] Diamond microparticles or carbon fiber whiskers, modified micro powder, and molten salt are mixed in a mass ratio of 1-5:1:10-40 and reacted in a tube furnace at 850-1050℃ for 30-150 minutes under the protection of high-purity argon. After cooling to room temperature, the mixture is washed with water, acid-washed, washed with water, filtered three times, and dried to obtain modified diamond and modified carbon fiber with metal coating or metal carbide coating.
[0017] Preparation of S3 dual-carbon material-enhanced gallium-based composite thermal grease;
[0018] Modified diamond and modified carbon fiber are added to gallium-based liquid metal, mixed, heated, stirred, compressed, and ground to obtain the dual-carbon material-reinforced gallium-based composite thermal grease.
[0019] Furthermore, in the preparation step of gallium-based liquid metal in step S1, the mixing environment is an oxygen-free environment, and the heating temperature is 250-300℃.
[0020] Furthermore, in step S1, the heating temperature is 300°C.
[0021] Furthermore, in step S1, the stirring time is 60 minutes.
[0022] Furthermore, the mass percentage of the gallium-based liquid metal in step S1 is 67:20.5:12.5, and the gallium-based liquid metal is Ga... 67 In 20.5 Sn 12.5 Ternary eutectic alloy, the melting point of ternary eutectic alloy is 10.2℃.
[0023] Furthermore, in the metallization modification step S2, the modified micro powder is titanium micro powder, the coating is titanium carbide coating, and the molten salt is a mixed salt of sodium chloride and potassium chloride in a mass ratio of 1:1.
[0024] Furthermore, in the metallization modification step S2, the diamond microparticles have a particle size of 50-100 μm; the carbon fiber whiskers have a length of 150-300 μm and a diameter of 5-10 μm; the titanium micropowder has a particle size of 1-10 μm; the mass ratio of the diamond microparticles or carbon fiber whiskers to the titanium micropowder is 1-5:1; the surface coating thickness of the modified diamond after metallization modification is 50 nm-2 μm; and the surface coating thickness of the modified carbon fiber after metallization modification is 50 nm-2 μm.
[0025] Furthermore, in step S2, the pickling solution is a hydrochloric acid solution with a mass concentration of 37%, the reaction temperature is 90°C, and the reaction time is 2 hours.
[0026] Furthermore, in step S2, the temperature for drying the powder is 70-100℃, and the drying time is 14-18h.
[0027] Furthermore, the specific steps of step three are as follows:
[0028] Gallium-based liquid metal, modified diamond, and modified carbon fiber in a volume ratio of 50-70:30-50:2-10 are sequentially mixed in a crucible and heated and stirred at 50-100℃ for 10-40 minutes in air until homogeneous, yielding a dual-carbon reinforced gallium-based composite thermal paste. Heating and stirring in air promotes the oxidation of the gallium-based liquid metal to form gallium oxide, facilitating rapid composite formation between titanium carbide and the gallium-based liquid metal. However, gallium oxide reduces thermal conductivity; therefore, after homogeneous mixing, the mixture should be immediately placed in a vacuum environment to prevent unnecessary oxide formation.
[0029] Compared with the prior art, the present invention has the following beneficial effects:
[0030] (1) In the above technical solution, titanium micro powder is used to metallize the surface of carbon material. By controlling the mass ratio of carbon material to titanium micro powder, the uniformity of titanium carbide coating on the surface of carbon material can be improved, and the coating thickness of modified carbon material can be adjusted.
[0031] (2) In the above technical solution, the modified carbon material is combined with gallium-based liquid metal in an air environment. The surface of the gallium-based liquid metal is easily oxidized to form gallium oxide. Gallium oxide is easy to adhere to and wet titanium carbide, thereby improving the wettability between the carbon material and the gallium-based liquid metal, helping the carbon material to combine with the gallium-based liquid metal, and improving the performance of the gallium-based composite thermal paste.
[0032] (3) In this embodiment of the invention, gallium indium tin liquid metal is selected as the matrix of the thermal interface material. The melting point of this gallium-based liquid metal is around 5-25°C, which makes the gallium-based metal liquid at room temperature. Liquid metal has both high thermal conductivity and high deformability, making it an ideal thermal interface material. Adding diamond and carbon fiber as thermally conductive reinforcing particles can improve thermal conductivity while mitigating the problem of blocked pumping.
[0033] (4) By adding modified diamond and modified carbon fiber to gallium-based liquid metal, diamond and carbon fiber are uniformly dispersed in liquid metal and overlapped to form a ball-and-stick thermal conductive structure, forming a good thermal conductive path and exhibiting a high thermal conductivity.
[0034] (5) Modified diamond and modified carbon fiber are obtained by metallization modification, and a metal coating or metal carbide coating is formed on the surface, which can significantly improve the surface wettability of diamond particles, carbon fiber whiskers and liquid metal. Attached Figure Description
[0035] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.
[0036] Figure 1 This is a SEM image of the modified diamond obtained in Embodiment 1 of the present invention;
[0037] Figure 2 The image shows a SEM image of the modified carbon fiber obtained in Example 1 of this invention.
[0038] Figure 3 The graph shows a comparison of the thermal conductivity of the gallium-based composite thermal pastes obtained in Examples 1, 2, 3, 4 and Comparative Example 1. Detailed Implementation
[0039] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions in specific embodiments of the present invention will be clearly and completely described below.
[0040] The following is a detailed description of a dual-carbon material-reinforced gallium-based composite thermal grease, its preparation method, and its application, based on embodiments of this application.
[0041] Example 1
[0042] This application provides a method for preparing a gallium-based composite thermal conductive paste reinforced with dual carbon materials, comprising the following steps:
[0043] Step S1, Preparation of gallium-based liquid metal:
[0044] Using a high-precision balance, weigh liquid gallium, indium granules, and tin powder in a mass percentage ratio of 67:20.5:12.5 and place them in a crucible. Heat and stir in a vacuum environment until the temperature reaches 300°C and the mixture is stirred for 60 minutes until it becomes homogeneous. The liquid metal can then be obtained. After cooling to room temperature, store it in an oxygen-free environment for later use. The melting point of the liquid metal is 10.2°C.
[0045] Step S2, metallization modification:
[0046] Diamond microparticles, titanium micropowder, and molten salt (a mixture of sodium chloride and potassium chloride in a 1:1 mass ratio) were mixed in a mass ratio of 2.5:1:35. Under high-purity argon protection, the mixture was heated from room temperature at a rate of 5°C / min, reaching 950°C, and then subjected to a salt bath treatment for 2 hours to form a metal carbide coating on the surface of the diamond microparticles. The mixture was then cooled in the furnace, followed by water washing, acid washing, and then water washing and filtration three times. The water washing solution was distilled water, and the acid washing solution was a 37% hydrochloric acid solution. The acid washing reaction temperature was 90°C, and the reaction time was 2 hours. Finally, the powder was dried at 80°C for 14 hours to obtain modified diamond with a metallized titanium carbide coating.
[0047] Carbon fiber whiskers, titanium micropowder, and molten salt (a mixture of sodium chloride and potassium chloride in a 1:1 mass ratio) were mixed in a mass ratio of 3:1:40. Under high-purity argon protection, the mixture was heated from room temperature at a rate of 5°C / min, reaching 850°C, and then subjected to a salt bath treatment for 2 hours to form a metal carbide coating on the surface of the carbon fiber whiskers. The mixture was then cooled in the furnace, followed by water washing, acid washing, and then water washing and filtration three times. The water washing solution was distilled water, and the acid washing solution was a 37% hydrochloric acid solution. The acid washing reaction temperature was 90°C, and the reaction time was 2 hours. Finally, the powder was dried at 80°C for 14 hours to obtain modified carbon fibers with a metallized titanium carbide coating.
[0048] Step S3, Preparation of gallium-based composite thermal paste reinforced with dual carbon materials:
[0049] Gallium-based liquid metal, modified diamond, and modified carbon fiber in a volume ratio of 50:44:6 were mixed sequentially in a crucible and heated and stirred at 50°C for 30 minutes in air until the mixture was homogeneous, thus obtaining a gallium-based composite thermal paste reinforced with dual carbon materials.
[0050] Figure 1 The image shows a SEM image of the modified diamond obtained in Example 1 of this invention. As can be seen from the image, a uniform and dense titanium carbide coating is formed on the surface of the diamond particles. Figure 2 The image shows a SEM image of the modified carbon fiber obtained in Example 1 of this invention. As can be seen from the image, a uniform and dense titanium carbide coating is formed on the surface of the carbon fiber whiskers.
[0051] Example 2
[0052] This application provides a dual-carbon material reinforced gallium-based composite thermal grease, the preparation method of which is roughly the same as that of Example 1, except that in step three, gallium-based liquid metal, modified diamond and modified carbon fiber in a volume ratio of 50:46:4 are mixed evenly in sequence to obtain dual-carbon material reinforced gallium-based composite thermal grease.
[0053] Example 3
[0054] This application provides a dual-carbon material reinforced gallium-based composite thermal grease, the preparation method of which is roughly the same as that of Example 1, except that in step three, gallium-based liquid metal, modified diamond and modified carbon fiber in a volume ratio of 50:42:8 are mixed evenly in sequence to obtain dual-carbon material reinforced gallium-based composite thermal grease.
[0055] Example 4
[0056] This application provides a dual-carbon material-reinforced gallium-based composite thermal grease, the preparation method of which is roughly the same as that of Example 1, except that in step three, gallium-based liquid metal, modified diamond and modified carbon fiber in a volume ratio of 50:48:2 are mixed evenly in sequence to obtain dual-carbon material-reinforced gallium-based composite thermal grease.
[0057] Comparative Example 1.
[0058] This application provides a comparative example of a gallium-based composite thermal grease reinforced with dual carbon materials. The preparation method is roughly the same as that in Example 4, except that: there is no metallization modification process in step two; in step three, gallium-based liquid metal, diamond microparticles and carbon fiber whiskers in a volume ratio of 50:48:2 are mixed evenly in sequence to obtain gallium-based composite thermal grease reinforced with dual carbon materials.
[0059] Figure 3The graphs show the thermal conductivity of gallium-based composite thermal pastes obtained in Examples 1, 2, 3, 4 and Comparative Example 1. The comparison in the graphs shows that the addition of diamond and carbon fibers with titanium carbide coating can significantly improve the thermal conductivity of gallium-based composite thermal pastes.
[0060] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A gallium-based composite thermal grease reinforced with dual carbon materials, characterized in that, The thermal paste comprises gallium-based liquid metal and inorganic thermally conductive carbon material filler.
2. The dual-carbon material-reinforced gallium-based composite thermal grease according to claim 1, characterized in that, The gallium-based liquid metal is one or more of gallium, indium, tin, zinc, antimony, bismuth, cadmium, and lead.
3. The dual-carbon material reinforced gallium-based composite thermal grease according to claim 1, characterized in that, The inorganic thermally conductive carbon material filler is modified diamond and modified carbon fiber; wherein, the modified diamond includes diamond microparticles and a metal coating or metal carbide coating on the surface of the diamond microparticles, and the modified carbon fiber includes carbon fiber whiskers and a metal coating or metal carbide coating on the surface of the carbon fiber whiskers.
4. The dual-carbon material reinforced gallium-based composite thermal grease according to claim 3, characterized in that, The metal coating is at least one of titanium, chromium, and tungsten, and the metal carbide coating is at least one of titanium carbide, chromium carbide, and tungsten carbide.
5. The dual-carbon material reinforced gallium-based composite thermal grease according to claim 1, characterized in that, The raw materials of the gallium-based liquid metal are composed of liquid gallium, indium particles and tin powder in a mass ratio of 65-70:18-23:10-15, and the volume ratio of the gallium-based liquid metal to the diamond and the carbon fiber is 50-70:30-50:2-10.
6. The method for preparing the dual-carbon material-reinforced gallium-based composite thermal grease as described in any one of claims 1 to 5, characterized in that, Includes the following steps: Preparation of Si gallium-based liquid metal; Weigh out liquid gallium, indium granules, and tin powder, mix them, and heat and stir to obtain gallium-based liquid metal; S2 metallization modification; Diamond microparticles or carbon fiber whiskers, modified micro powder, and molten salt are mixed in a mass ratio of 1-5:1:10-40 and reacted in a tube furnace at 850-1050 ℃ for 30-150 min under the protection of high-purity argon. After cooling to room temperature, the mixture is washed with water, acid-washed, washed with water, filtered three times, and dried to obtain modified diamond and modified carbon fiber with metal coating or metal carbide coating. Preparation of S3 dual-carbon material-enhanced gallium-based composite thermal grease; Modified diamond and modified carbon fiber are added to gallium-based liquid metal, mixed, heated, stirred, compressed, and ground to obtain the dual-carbon material-reinforced gallium-based composite thermal grease.
7. The preparation method according to claim 6, characterized in that, In the preparation step of gallium-based liquid metal in step S1, the mixing environment is an oxygen-free environment, and the heating temperature is 250-300 ℃.
8. The preparation method according to claim 6, characterized in that, In the metallization modification step S2, the modified micro powder is titanium micro powder, the coating is titanium carbide coating, and the molten salt is a mixed salt of sodium chloride and potassium chloride in a mass ratio of 1:
1.
9. The preparation method according to claim 6, characterized in that, In the metallization modification step S2, the diamond microparticles have a particle size of 50-100 μm; the carbon fiber whiskers have a length of 150-300 μm and a diameter of 5-10 μm; the titanium micropowder has a particle size of 1-10 μm; the mass ratio of the diamond microparticles or carbon fiber whiskers to the titanium micropowder is 1-5:1; the surface coating thickness of the modified diamond after metallization modification is 50 nm-2 μm; and the surface coating thickness of the modified carbon fiber after metallization modification is 50 nm-2 μm.
10. The preparation method according to claim 6, characterized in that, The preparation of the dual-carbon material-enhanced gallium-based composite thermal paste in step S3 includes the following steps: the mixing process is carried out in an air environment, and the mixture is heated and stirred at 50-100 °C for 10-40 min.